费米在球状星团中探测了一颗发光的γ射线脉冲星
Science (New York, N.Y.)
|November 5, 2011
概括
费米望远镜检测到高能马射线脉冲来自NGC 6624中的脉冲星J1823-3021A. 这颗毫秒脉冲星 (MSP) 显示了创纪录的亮度,这表明它.
科学领域:
- *高能天体物理学 *高能天体物理学
- * 马射线天文学 马射线天文学
- * 脉冲星物理学
背景情况:
- *球状星团是密集的恒星系统,包含脉冲星.
- *毫秒脉冲星 (MSP) 是快速旋转的中子星.
- *以前的估计表明,在NGC 6624中约有100个马射线MSP.
研究的目的:
- * 报告使用费米大面积望远镜从J1823-3021A探测到马射线脉冲.
- * 描述这颗脉冲星的特性及其对星团辐射的贡献.
- *根据新的观测,重新评估球状集群中的MSP种群.
主要方法:
- *利用费米大面积望远镜的数据来检测马射线脉冲 (>100 MeV).
- *分析了脉冲星J1823-3021A及其宿主球状星团NGC 6624.
- * 计算了马射线发光度,并将其与已知的MSP属性进行比较.
主要成果:
- *显著检测到 (~7 σ) 来自J1823-3021A的马射线脉冲.
- * 观测到MSP (8.4 ± 1.6 × 10^34 ergs/s) 的纪录高的马射线亮度,主导集群发射.
- * 限制了NGC 6624中的马射线MSP的数量为32,修改了之前的估计.
结论:
- *高亮度表明J1823-3021A的回转是内在的,这表明MSP具有很大的磁场和年轻年龄.
- *像J1823-3021A这样的异常MSP可能以与正常MSP相比的速度形成.
- * 修订了对球状星团中MSP种群及其形成机制的理解.
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